Chelsea are expected to have the option of re-signing Nathan Ake once the defender completes a switch to Bournemouth.
The 22-year-old Holland international was recalled from loan at Bournemouth in January by Chelsea head coach Antonio Conte.
But now the Chelsea boss is willing to accede to Ake's request to play regularly, with the Cherries hoping to complete a deal. That could be as soon as Thursday, Press Association Sport understands.
The fee for Ake, who can play in central defence, at left-back or midfield, is reportedly £20million and includes a buy-back clause.
Premier League champions Chelsea have learnt from the sales of a host of young talent in recent seasons by inserting options to recapture young players.
Bertrand Traore last week moved to Lyon for Â£10million, but there is a contract provision for Chelsea to re-sign the Burkina Faso international at a later date if they wish to do so.
Striker Tammy Abraham is anticipated to be moving to Swansea on a season-long loan, once the England Under-21 striker has signed a new contract to commit to Chelsea.
The Blues are likely to wait to announce any incoming players in the summer transfer market, with Willy Caballero set to be the first arrival after the window opens on Saturday.
Caballero, who is to be released from Manchester City this week, is to be back-up goalkeeper to Thibaut Courtois.